<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div class="container">
        <span class="item">1</span>
        <span class="item">2</span>
        <span class="item">3</span>
        <span class="item">4</span>
        <span class="item">5</span>
        <span class="item">6</span>
        <span class="item">7</span>
        <span class="item">8</span>
        <span class="item">9</span>
        <span class="item">7</span>
        <span class="item">8</span>
        <span class="item">9</span>
    </div>
    <style>
        .container{
            display: inline-grid;
            grid-template-rows: repeat(3,200px);
            grid-template-columns: repeat(3,200px);
            /* 多出的单元格宽 200 搞 100 */
            grid-auto-rows: 100px;
            grid-auto-columns: 200px;
            gap: 10px;
            grid-template-areas: 'header header header'
                                 'left main right'
                                 'footer footer footer';
            background: cadetblue;
            height: 620px;
            width: 620px;
        }
        .item{
            background: bisque;
        }
        .item:first-child{
            /* left开始到 right 结束 */
            grid-column: 1 / right-end;
            /* 跨越两个单元格 */
            grid-row: header-start / span 2;
        }
    </style>
</body>
</html>